GM Service Manual Online
For 1990-2009 cars only

Low Engine Coolant Indicator Inoperative Diesel Only

Step

Action

Value(s)

Yes

No

1

Did you perform the Instrument Cluster System Check?

--

Go to Step 2

Go to Instrument Cluster System Check

2

  1. Ensure that the coolant level is below the coolant sensor.
  2. Disconnect the connector at the Low Coolant Level Sensor.
  3. Connect a J 39200 DMM (continuity) at the Low Coolant Level Sensor pins A and B.

Is continuity present?

--

Go to Step 4

Go to Step 3

3

Replace the Low Coolant Level Sensor. Refer to Surge Tank (Diesel) Replacement in Engine Cooling.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

4

  1. Disconnect the connector at the Low Coolant Level Indicator Module.
  2. Connect a J 39200 DMM (continuity) between cavity F of the Low Coolant Level Indicator Module connector and cavity A of the Low Coolant Level Sensor.

Is continuity present?

--

Go to Step 6

Go to Step 5

5

Locate and repair the short to ground in the CKT 1478 (LT GRN) wire between the Low Coolant Level Indicator Module and the Low Coolant Level Sensor. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

6

  1. Disconnect the connector at the I/P Cluster.
  2. Connect a J 39200 DMM (continuity) between the I/P Cluster connector cavity 25 and the Low Coolant Level Indicator Module connector cavity E.

Is continuity present?

--

Go to Step 8

Go to Step 7

7

Locate and repair the open in the CKT 68 (YEL/BLK) wire between the I/P Custer and the Low Coolant Level Indicator Module. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

8

  1. Connect a J 39200 DMM (continuity) between cavity C of the Low Coolant Level Indicator Module connector and ground.
  2. Connect a J 39200 DMM (continuity) between cavity B of the Low Coolant Level Sensor connector and ground.

Is continuity present?

--

Go to Step 10

Go to Step 9

9

Locate and repair the open in CKT 150 (BLK) between either the Low Coolant Level Indicator Module and ground or the Low Coolant Level Sensor and ground, which ever applies. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

10

  1. Connect a J 39200 DMM (volts) between cavity A of the Low Coolant Level Indicator Module connector and ground.
  2. Turn the ignition switch to the RUN position.

Is battery voltage present?

--

Go to Step 12

Go to Step 11

11

Locate and repair the open in CKT 39 (PNK) between the IP Fuse Block and the Low Coolant Level Indicator Module. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

12

  1. Re-install the I/P Cluster.
  2. Place the ignition switch in the RUN position.
  3. Connect a fused jumper wire between the Low Coolant Level Indicator Module connector cavity E and ground.

Does the low coolant indicator light?

--

Go to Step 13

Go to Step 14

13

Replace the Low Coolant Level Indicator Module. Refer to Coolant Level Module Replacement in Engine Cooling.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

14

Replace the I/P Cluster. Refer to Instrument Cluster Replacement .

Is the repair complete?

--

Go to Instrument Cluster System Check

--